L67 Loose inlet manifold bolts.

[RoyV]

Hi there, just a question for the experienced.
I seem to have water in my oil and vise versa, could loose bolts on the inlet manifold cause this issue and also create pressure in the water system.

I first assumed the head gasket's was gone.

When i removed supercharger etc I noticed the bolts holding down the inlet manifold were loose (Some finger tight).

Thanks in advance for any help.

 

[losh1971]

Id say the gasket is hard and worn out rather than just loose bolts. I just replaced mine last week. My Buick has more power and is not running lean as it was sucking air. The water ports were also allowing oil ingression. Either way it really needs to come off as the ports will have sludge partially blocking them up.

 

[Immortality]

Loose bolts yes definitely an issue.

those bolts are only torqued to 14Nm if memory serves so they need some sort of thread locker to stop em coming loose. As above, it maybe a good time to do the LIM gaskets whilst you are there.

 

[RoyV]

Id say the gasket is hard and worn out rather than just loose bolts. I just replaced mine last week. My Buick has more power and is not running lean as it was sucking air. The water ports were also allowing oil ingression. Either way it really needs to come off as the ports will have sludge partially blocking them up.

Thanks for clarifying my theory, I have ordered the Inlet manifold gasket kit and rebuild it all from there.
A bit of relief not having to remove the heads.

 

[losh1971]

Loose bolts yes definitely an issue.

those bolts are only torqued to 14Nm if memory serves so they need some sort of thread locker to stop em coming loose. As above, it maybe a good time to do the LIM gaskets whilst you are there.

slightly different engine but on the Buick some of those bolts come into contact with coolant. Because of that i put RTV on all of them. I tried getting thread sealant as that acts as a mild thread lock as well as sealant. Since i couldn't get any i used RTV which helps seal. I done mine up nice and firm with a 3/8 spanner as you can't really get a torque wrech on most of the bolts on the Buick.

 

[losh1971]

Another thing I did was to spray RP7 on the manifild gaskets. This helps the manifold slide easier without damaging the blue rubber on the gaskets when you line up the bolt holes.

 

[RoyV]

Ok here is a Silly question, I do not remember removing the blue seals. What are these meant for?

 

[losh1971]

They sit on the front and back lips. I put some sealant on the four corners.

 

[losh1971]

The ones you take off might be orange.